Multiple manifold headbox



Oct. 3, 1967 l k a l X 1 x g l I J. J. KlLlAN MULTIPLE MANIFOLD HEADBOX Filed June 24, 1964 Fig.4

INVENTOR. JOSEPH J. KILIAN L ATTORNEY United States Patent 3,345,254 MULTIPLE MANIFOLD HEADBOX Joseph J. Kilian, Covington, Va., assignor, by mesne assignments, to The Black Clawson Company, New York, N.Y., a corporation of Ohio Filed June 24, 1964, Ser. No. 377,607 7 Claims. (Cl. 162343) The present invention relates to a unique headbox construction which permits control of the characteristics of the slice jet issuing therefrom.

In the application of William H. Burgess, Jr., and Girard L. Calehuif, Ser. No. 376,699, filed June 22, 1964, and entitled Bunched Tube Headbox, a headbox is disclosed which, through the use of a plurality of small diameter tubes interconnecting a manifold and slice-assembly, provides a slice jet free of cross flows and other velocity irregularities and maintains the fibers Within the stock uniformly dispersed.

The present invention represents an improvement over the above noted headbox and, while incorporating the principle of a confined flow path from supply source to slice, provides means whereby the character, consistency, velocity and pressure of portions of the slice jet may be varied to obtain the type of web desired.

More specifically, the headbox of the present invention utilizes a plurality of manifolds with a multiplicity of comparatively small diameter tubes leading from said manifolds to a single slice assembly.

Thus, by varying the type and/or consistency of the stock suplied to one or more of the manifolds and disposing the outlet ends of the tubes in the desired arrangement, a multi-layer slice jet may be provided.

Additionally, through the use of the headbox of the present invention, the pressure and/ or velocity at selected points along the slice may be varied for such purposes as, for example, controlling web edge formation.

In many instances it may be desirable to obtain intermixing of the jets issuing from the small diameter tubes. Through the multiple manifold system of the present invention, blending of the jets at the slice to achieve this end may be attained by varying the pressure and/ or velocity of adjacent jets at the slice; thereby altering the relative stability between jets which is characteristic of the bunched tube headbox.

These and other features and advantages of the present invention will become apparent from the following detailed description wherein:

FIGURE 1 is a plan view of the multiple manifold system of the present invention;

FIGURE 2 is an elevational view thereof;

FIGURE 3 is a sectional view taken on line 33 of FIGURE 2 illustrating one way in which the multiple manifold headbox may be utilized to vary portions of the slice jet; and

FIGURE 4 is a view similar to FIGURE 3 showing another manner in which the multiple manifold system may be used. 7

Referring to FIGURES 1 and 2 of the drawings, there is shown the multiple manifold headbox of the present invention including a plurality of manifolds 1, 2, 3 and 4, a multiplicity of tubes 5, which may be substantially square in cross section, leading from the manifolds, and a slice assembly 6.

Manifolds 1-4 each includes top and bottom Walls 7 and 8 and sidewalls 9 and 10. As will be seen from FIG- URES 1 and 2, the manifolds may taper from a large dimension adjacent their inlet ends 11 to a smaller dimension adjacent their outlet ends 12. In this manner the pressure at all points along the length of the manifolds 3,345,254 v Patented Oct. 3, 1967 may be maintained fairly uniform and uniform flow through the tubes 5 thereby enhanced. Sidewall 10 of each of the manifolds is provided with a series of apertures 13 formed therein and secured to sidewall 10 in overlying relationship thereto is an inlet plate member 14. Each inlet plate 14 also has a series of apertures 15, which, when the plate 14 is secured to sidewall 10, are in substantial registration with the apertures 13. Attached to each inlet plate member 14 are the tubes 5, which may, as shown, extend substantially perpendicularly from the manifolds. Intermediate their lengths the tubes 5 may then converge to a parallel, juxtaposed relationship adjacent the slice assembly. At their outlet ends the tubes 5 are joined to an outlet plate member 16 having a series of apertures 17 therein with the sidewalls of the outlet ends of the tubes 5 each surrounding one of said apertures 17. Outlet plate member 16 is secured by means of bolts or the like, 18, to the back wall 19 and a downwardly extending flange 20 of the slice assembly 6. Additionally, slice assembly 6 may comprise sidewalls 21 and 22, a bottom wall 23 and an adjustable slice lip 24.

It will be apparent from the above description that stock entering each of the manifolds through their inlet ends 11, flows therethrough towards the outlet end 12. As the stock passes through each manifold, a portion thereof is tapped off in the form of small streams through the apertures 13 and thence, through the apertures 15 in inlet plate member 14. These smaller streams are then immediately confined in the small diameter tubes 5 and maintained in this confined state until their ejection through the apertures 17 in outlet plate member 16. By thus confining the smaller streams in the small diameter tubes throughout their travel through the headbox, velocity differentials and the like are substantially eliminated. Additionally, the use of small diameter tubes permits the establishment of a fine scale turbulence in each tube and maintains the fibers in each stream uniformly dispersed throughout. Since the tubes, at their outlet ends and for a portion of their lengths upstream thereof, are arranged in closely spaced, parallel relationship, the plurality of small jets issue at the slice assembly as a single, compound jet with substantially all flow irregularities dampened out and the fibers therein uniformly dispersed. Thus, the jet delivered to the forming member may be substantially homogenous and poor web formation and caliper differentials avoided.

Because of the effectiveness of the tubes 5 in dampening out pressure surges, eddies, cross flows and the like,

the jets issuing from the outlet ends of the tubes are substantially stable with respect to one another and inter-jet mixing is, therefore, minimal. This characteristic may be used to great advantage with the multiple manifold system of the present invention to produce a multi-layer web.

As is well known to those skilled in the art, conventional practice in forming a multi-layer web generally entails the positioning of one or more secondary headboxes over the forming member downstream of the primary headbox. Each headbox then delivers the type and/or consistency of stock desired to form a particular layer of the web. In this manner, a base layer of inexpensive material may be covered on one or both sides thereof with higher quality layers for improved appearance, printability, density and the like. While the use of secondary headboxes, therefore, provides many advantages, it is also subject to some serious disadvantages. Thus, equipment costs are obviously higher when a plurality of headboxes are' used.'Additionally, since secondary headboxes must extend over the forming member,.the problem of structural support is a troublesome one and condensate and headbox onto the partially formed web and prevent its proper formation. Through the headbox of the present invention, however, a multi-layer web may be formed with a single headbox and the above noted problems obviated. Thus, as seen in FIGURES 2 and 3, stock of a first type and/ or consistency may be supplied to tubes 1 and 2 by manifolds 1 and 2, while tubes 3 and 4' may be supplied by manifolds 3 and 4 with a stock of a second type and/ or consistency. The resulting compound jet will, therefore, in effect, be a two layer jet which will, when deposited on the forming member, form a two layer web. Because the individual jets and hence, the two horizontal rows of jets, will be substantially stable with respect to each other, each of the two layers will retain its individuality as it is deposited on the forming member. This condition will, of course, be further enhanced by the fact that the fiber network within each jet contributes, to some extent, to the integrity thereof.

Another manner in which the multiple manifold system of the present invention finds utility is in the control of web edge formation. Thus, since the stock deposited on the forming member is generally a relatively low consistency fiber-liquid suspension, the stock tends to spread upon deposition, resulting in ragged edges which are usually trimmed off before further processing. By means of a multiple manifold system, however, edge formation can, to a great extent, be controlled by varying the pressures and velocities across the slice. Referring to FIGURES 2 and 4 it will be seen that stock, at a first pressure and/ or consistency may be delivered through tubes 2 and 3' from manifolds 2 and 3, respectively, while manifolds 1 and 4 may deliver stock at a second consistency and/ or higher pressure to tubes 1' and 4', respectively. In this manner, the body of the slice jet, supplied by tubes 1 and 4, is confined within the relatively high pressure areas created by the higher pressure jets issuing from tubes 2 and 3', and spreading of the slice jet is thereby decreased.

While the foregoing has been concerned with utilizing the inter-jet stability and relatively slight degree of intermixing associated with the present headbox, in some instances it may be desirable to alter the relative stability of the jets and promote intermixing thereof. This may be accomplished in the multiple manifold system of the present invention by varying the pressure at which the stock is delivered to tubes adjacent to each other at the outlet plate. In this manner the identity, and hence the relative stability, of adjacent jets is altered and increased inter-jet blending obtained. Referring to FIGURES 2 and 3 of the drawings, it will be seen that this may conveniently be accomplished by supplying stock to manifolds 1 and 3 at a first pressure and stock to manifolds 2 and 4 at a second, significantly different pressure. As a result it will be seen that tubes 1 and 3, which are fed by manifolds 1 and 3, respectively, will deliver stock at one pressure and tubes 2' and 4', fed by manifolds 2 and 4, respectively, will deliver stock at the second pressure. Since no two adjacent tubes will, therefore, be at the same pressure, the inter-jet stability will be altered and adjacent jets effectively intermixed.

From the above description it will be apparent that applicant has devised a unique headbox which permits great flexibility in operation. While in the specific embodiment described the manifolds are arranged in two groups with the tubes from each group merging to form a single, horizontally extending row of tubes at the slice assembly, it will readily be seen that many specific features of the invention, such as the number and arrangement of manifolds and tubes, as well as the configurations thereof, may be varied within the scope of the appended claims.

I claim:

1. Headbox apparatus for delivering paper making stock simultaneously from a plurality of sources to a forming member of a paper machine, comprising:

(a) a plurality of manifolds each adapted to receive a supply of paper making stock for delivering to the forming member,

(b) a plurality of relatively small diameter tubes extending from each of said manifolds and in fluid communication therewith,

(c) a slice assembly including slice lips defining a discharge outlet slot to the forming member, and

((1) said tubes terminating at and in fluid communication with said slice assembly and being arranged in at least one row extending parallel with and of substantially the same lentgh as said outlet slot.

2. The apparatus of claim 1 wherein:

(a) Said tubes extend upstream from said slice assembly in parallel, juxtaposed relationship for at least a portion of their lengths.

3. The apparatus of claim 2 wherein:

(a) Said tubes are arranged at the ends thereof adjacent said slice assembly in a plurality of vertically stacked, horizontally extending rows for said portion of their lengths.

4. The apparatus of claim 3 wherein:

(a) said manifolds are arranged in groups, and

(b) the tubes extending from each group of manifolds form at least one of said horizontally extending rows.

5. In a multiple manifold headbox assembly for deliving paper making stock through an outlet slot to the forming member of a paper machine and wherein a plurality of small diameter tubes are supplied by said manifolds with stock and said tubes are arranged adjacent their outlet ends in parallel, juxtaposed relationship and in at least one row extending parallel with and of substantially the same length as the outlet slot, the method which comprises:

(a) supplying stock to some of said tubes at a first pressure, and

(b) supplying a liquid-fiber suspension to others of said tubes at a second pressure different from said first pressure.

6. In a multiple manifold headbox assembly for delivering paper making stock through an outlet slot to the forming member of a paper machine and wherein a plurality of small diameter tubes are supplied by said manifolds with stock and said tubes are arranged adjacent their outlet ends in a plurality of vertically stacked, horizontally extending rows parallel with and of substantially the same length as the outlet slot, the method which comprises:

(a) supplying stock of a first type to at least one of the manifolds and (b) supplying stock of a second type to at least one other of the manifolds.

7. Headbox apparatus for delivering paper making stock simultaneously from a plurality of sources to a forming member of a paper machine, comprising:

(a) a plurality of elongated manifolds each including a top wall, a bottom wall and a pair of sidewalls,

(b) one of said sidewalls in each of said manifolds having a plurality of apertures formed therein,

(c) a plurality of tubes attached to and extending from said apertures respectively,

(d) said tubes extending from said manifolds in spaced parallel relationship for a first portion of their lengths,

(e) said tubes extending in converging relationship for a second portion of their lengths adjoining said first portions,

(f) said tubes extending in parallel juxtaposed relationship for a third portion of their lengths adjoining said second portion and terminating in outlet ends remote from said second portions,

(g) an outlet plate member having a plurality of apertures formed therein,

(h) a slice assembly including an outlet plate member and a pair of slice lips defining a discharge slot,

(i) said outlet plate member having a plurality of apertures formed therein and defining at least one row extending parallel with and of substantially the same length as said outlet slot, and

(1 said outlet ends of said tubes directly connecting with said apertures in said outlet plate respectively 5 to deliver stock simultaneously through all of said apertures to said discharge slot.

6 References Cited UNITED STATES PATENTS 2,693,739 11/1954 Okawa et a1. l62302 X 3,190,790 6/1965 Ploetz et a1. 162343 X DONALL H. SYLVESTER, Primary Examiner. I. H. NEWSOME, Assistant Examiner. 

1. HEADBOX APPARATUS FOR DELIVERING PAPER MAKING STOCK SIMULTANEOUSLY FROM A PLURALITY OF SOURCES TO A FORMING MEMBER OF A PAPER MACHINE, COMPRISING: (A) A PLURALITY OF MANIFOLDS EACH ADAPTED TO RECEIVE A SUPPLY OF PAPER MAKING STOCK FOR DELIVERING TO THE FORMING MEMBER, (B) A PLURALITY OF RELATIVELY SMALL DIAMETER TUBES EXTENDING FROM EACH OF SAID MANIFOLDS AND IN FLUID COMMUNICATION THEREWITH, (C) A SLICE ASSEMBLY INCLUDING SLICE LIPS DEFINING A DISCHARGE OUTLET SLOT TO THE FORMING MEMBER, AND (D) SAID TUBES TERMINATING AT AND IN FLUID COMMUNICATION WITH SAID SLICE ASSEMBLY AND BEING ARRANGED IN AT LEAST ONE ROW EXTENDING PARALLEL WITH AND OF SUBSTANTIALLY THE SAME LENGTH AS SAID OUTLET SLOT. 